In-Bi low-temperature SLID bonding

In-Bi SLID bonding on Au pads, with bonding temperature as low as 90 °C, is demonstrated. The resulting bondline consists of a structure of Au / Au-In intermetallics / Au, with inclusions of Bi or BiIn
2
(bonding temperature dependent). Au and Au-In intermetallics are stable to temperatures as high as 450 °C, implying that In-Bi low-temperature SLID bonding on Au pads has potential to be solid up to 450 °C. This opens for reliable metallurgical bonding of temperature-sensitive materials such as poled piezoelectric materials, ferromagnetic materials and polymers. Preliminary die shear measurements demonstrate that strong bonds can be achieved.